Polymer flocculation of calcite: Population balance model

Autor:	Phillip D. Fawell, Alex R. Heath, Parisa A. Bahri, J.B. Farrow
Rok vydání:	2006
Předmět:	chemistry.chemical_classification Flocculation education.field_of_study Environmental Engineering Chemistry General Chemical Engineering Kinetics Population Thermodynamics Mineralogy Polymer Pipe flow Adsorption Breakage Particle size education Biotechnology
Zdroj:	AIChE Journal. 52:1641-1653
ISSN:	1547-5905 0001-1541
Popis:	A population balance (PB) model is used to describe the aggregation/breakage kinetics of calcite flocculation in turbulent pipe flow. The model describes simultaneous aggregation and breakage, and accounts for likely process variables: fluid shear, flocculant dosage, primary particle size and solid fraction, using four fitted parameters. Particle collision is described by the turbulent collision kernel of Saffman and Turner,1 however, the capture efficiency (α) is initially set to equal zero until the point of flocculant addition, then increases rapidly as described by an equation accounting for flocculant mixing/adsorption. Particles aggregated by high-molecular weight polymer flocculant typically do not achieve a steady-state aggregate size, where the rates of aggregation and breakage are equal. Instead, the aggregate size decreases gradually due to polymer chain scission or rearrangement on repeated aggregation/breakage. This phenomenon is accounted for in the model by a flocculant strength degradation term.
Databáze:	OpenAIRE
Externí odkaz:	https://explore.openaire.eu/search/publication?articleId=doi_________::b400a098a869f95f391b5a546e5d5a8d https://doi.org/10.1002/aic.10749 Zobrazit plný text záznamu Plný text